Coaxial circuit shifter



w. A. ETTER 3,144,538 COAXIAL CIRCUIT SHIFTER Filed June 7, 1962 3 Sheets-Sheet 1 WILLIAM A. ETTER ATTORNEY Aug. 11, 1964 w. A. ETTER COAXIAL CIRCUIT SHIFTER Filed June 7, 1962 3 Sheets-Sheet 2 TO NEXT /VVHORIZONTAL- SHIFTER OR GROUND TO NEXT LOWER SHIFTER ON VERTIO OR GROUND INVENTOR, I WILLIAM A. ETTER Mild/ W5 ATTORNEY.

11, 1964 w. A. ETTER 3,144,538

COAXIAL CIRCUIT SHIF'TER Filed June 7, 1962 5 Sheets-Sheet 3 FIG. 7

RECEIVER RECEIVER RECEIVER INVENTOR, WILLIAM A. ETTER BY/ZW ATTORNEY,

United States Patent tary of the Army Filed .lune 7, 1962, Ser. No. 200,893 7 Claims. (Cl. 200153) (Granted under Title 35, US. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates generally to high frequency switches, and more particularly to circuit shifters for use in very high frequency circuit arrangements.

The present invention provides a novel structure whereby a coaxial line may be selectively shifted from one coaxial line to another coaxial line without utilizing the switching methods of the prior art. The switches of the prior art involve either a moving armature which disconnects the center conductor of one coaxial line and connects it to a center conductor of a second coaxial line, or the physical movement of a section of the inner conductor from one line to another line. In each of these prior art methods the incoming and outgoing lines are terminated at fixed points on the switch housing with some internal action performing the switching.

In the embodiments of the invention hereinafter described in connection with the appended drawings a first coaxial line is terminated at a movable member, and the lines to which the first line may be selectively connected are terminated at a fixed member. The carriage or movable member is moved from one position to another position through the action of a solenoid to shift the first line from a connection with a second line to a connection with a third line. Since the entire coaxial line is, in effect, shifted from one circuit to another circuit, many of the disadvantages of prior art coaxial switches are overcome. The voltage standing wave ratio (VSWR) due to the presence of a switch is virtually eliminated; and the cross talk, which is so prevalent due to switches used in very high frequency circuits, is practically non-existent. Other features of the circuit shifter of the present invention are its compactness, economy of manufacture, low power requirements for remote-control purposes, and its wide variety of applications in very high frequency circuit configurations. The circuit shifter is particularly applicable for use in cross-bar arrangements wherein any one of a plurality of radio recievers, or low-power radio transmitters, are to be selectively connected to any one of a number of antennas from a remote-control point.

It is accordingly a principal object of the present invention to provide a novel and useful circuit shifting device.

Another object of the invention is to provide a circuit shifting means having a reduced cross-talk characteristic.

It is a further object of the invention to provide means for selectively interconnecting coaxial circuits which is compact, economical and simple to produce and which may be controlled by electrical, or, if desired, by mechanical means.

' Other objects and features of the invention will become apparent to those skilled in the art as the disclosure is made in the following detailed description of a preferred embodiment of the invention as illustrated in the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof and wherein:

FIGURE 1 is a plan view of a coaxial circuit shifter in accordance with the invention;

FIGURE 2 is a cross-sectional view of FIGURE 1 as taken along the line 2-2;

. in connection with FIGURE 3.

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FIGURE 3 is a fragmentary cross-sectional view of a portion of FIGURE 1 used in describing a detail of the invention;

FIGURE 4 is a showing of a further embodiment of the invention;

FIGURE 5 is a cross-sectional showing of a coaxial connector which may be used in the practice of the invention;

FIGURE 6 illustrates an arrangement of a plurality of circuit shifters; and

FIGURE 7 illustrates schematically a cross-bar arrangement utilizing circuit shifters of the present invention.

The embodiment illustrated by FIGURE 1 shows a circuit shifter comprising a bottom plate or track 11 made preferably of a ferrous non-corrosive material such as stainless steel, which is fastened to a mounting plate 10. Mounted on track 11 are three elements 19, 20 and 21. Coaxial element 21 is a grounding means to be described The contacting or switching portions of the center conductors of elements 16, 17 and 18 consist of silver-plated strong permanent magnets. The center conductor structure will be more fully described in connection with FIGURE 2. Carriage 12 includes side plates 12a which includes small guide pins 15.

Pins 15 travel in slots 14 and thus keep the carriage in proper relationship with bottom plate 11, End magnets 24 and 25 are mounted on the ends of the carriage 12 to provide the necessary traction during the movement of the carriage. In practice the carriage 12 and bottom plate 11 are machine-lapped so that all surfaces on the one touch all the surfaces of the other to prevent radio frequency leakage between the connecting elements. A solenoid 28 provides the switching force through the action of plunger 22. A switch 23, including contacts 23a and 23b is provided to complete circuit 27 through the action of plunger 22 when the solenoid is energized. Power for the operation of solenoid 28 is provided through leads 26. Spring 13 acts to return the carriage to its original or initial position when the solenoid is de-energized.

It will be noted that the spacing between 19-20 and 20-21 is equal. This spacing is also equal to the distance of travel of contact-carrying carriage 12. Therefore, when solenoid 28 is energized, elements 16, 17, 18 line up with elements 19, 20, 21 respectively. When solenoid 23 is de-energized, spring 13 draws carriage 12 to the left by an amount equal to the spacing between elements 19-20 or 20-21. At this time elements 19, 20 are axially aligned with elements 17, 18 respectively.

FIGURE 2 illustrates, in cross section, the internal structure of connectors 17 and 20 of FIGURE 1 taken along line 2-2. The center conductor 34 of connector 17 comprises a permanent magnet portion 30 and a coupling portion 32. Conductor 34 may consist of a unitary member in which the end portion and the coupling area are silver plated; or it may comprise a lower magnet portion and an upper coupling portion of different material. The structure of connector 20 comprises a center conductor 31 which includes a coupling portion 31a and a movable member 29. The cup-like movable member 29 is made of a ferrous material silver-plated in the region of contact, and is arranged in a telescopic relationship with the main portion 31b of the center conductor 31.

Flexible wires 33 are provided to insure a more positive connection between the movable portion and the coupling portion 31a of center conductor 31. The contacting faces of 34 and 29 are machined to provide a good contact area, and are silver-plated to provide good conductivity.

The internal structure of connector 18 and shorting element 21 is illustrated by FIGURE 3. The center elements of 18 comprise a coupling element 38 in electrical connection with a permanent magnet member 37. The center conductor of plug 21 comprises an inner fixed portion 21a and a movable portion 35. The cup-like member is made of ferrous material and arranged in a telescopic relationship with the pin 210. Small flexible wires 36 are provided to insure a good electrical connection between elements 35 and 21a. The facing or contacting portions of elements 37 and 35 are machined for good contact area and silver-plated to provide a high degree of conductivity during contact. In practice it is desirable to flare or taper very slightly the bottom portion 39 of connector 18 for the purpose of pushing the cup-like member out of the way when the carriage is moved from one position to another.

The embodiment of the invention shown in FIGURE 4 employs a pair of camming plates 43 and 44 to elevate slightly the carriage 57 during its movement from one position to another. With the carriage 57 in the position shown, a circuit is completed between connectors 49 and 51, and 50 and 52, respectively. The inner conductor of connectors 49 and 50 incorporates a spring-loaded movable center element to provide for a positive contact with the inner conductors of connectors 51 and 52. FIG URE 5 illustrates one form of structure which may be employed for this purpose. When solenoid 54 is deenergized spring means 45 and 46 acting on the respective pins 47 and 48 on one side of the carriage, and corresponding springs and pins similarly arranged on the other side of the carriage (not shown) act to pull the carriage 57 to the position which will cause connector 50 to be in alignment with connector 51. The springs also provide a force urging the carriage 57 toward bottom plate 42. The circuit shifter is shown mounted on a portion of a relay rack 40 by means of bracket 41.

FIGURE 5 is a showing, in cross-section, of the internal structure of coaxial connector 58 which may be employed in the modification of the circuit shifter described in connection with FIGURE 4. In place of the magnetically-urged center element of FIGURES 2 and 3, a spring means 56 seated within the center conductor 53 operates to urge contact 58 toward the center conductor of connectors 52 or 51 of FIGURE 4. The center conductors of 52 and 51 may be of the form illustrated by element 34 of FIGURE 2 with the exception that they need not be of ferrous material.

The ease with which the circuit shifter may be utilized in an antenna-receiver switching system is depicted by FIGURE 6. Here shifters S1, S2 and S3 are arranged in a horizontal row mounted to a bracket 60 of a relay rack. Shifters S4, S5 and S6 are mounted in a horizontal row to a bracket 61 vertically below shifters S1, S2 and S3. Additional horizontal and vertical shifters may be added as indicated in the legend on FIGURE 6.

In the arrangement illustrated by FIGURE 6 any one of the antenna connectors A1, A2 or A3 may be connected in circuit with any one of the connectors leading to receivers R1, R2 or R3 by selectively operating the circuit shifters. In the position shown, shifter S3 is in its energized condition and connects A1 through cable 63, through cable 64, to cable 65 which in turn connects to R1. In the positions shown, A2 and A3 would be connected to ground. For purposes of clarity auxiliary elements such as solenoid control circuits and switch details have been omitted from FIGURE 6.

An antenna-receiver switching system which includes control switches is schematically illustrated in FIGURE 7. Although only three antennas, A1, A2 and A3; and three receivers, R1, R2 and R3 are shown, any number of antennas or receivers could be used.

Switches S70, S71, and S72 control shifters 70, 71, and 72 respectively; switches S73, S74 and S75 control shifters 73, 74 and 75 respectively; and switches S76, S77 and S78 control shifters 76, 77 and 78 respectively. Leads 89, 81 and 82 may be connected to additional horizontal shifters or to ground; and leads 83, 84 and 85 may be connected to additional vertical shifters or to ground. Switches $70-$78 would in most cases be mounted on a control panel located at some convenient place. Lead 98 is the common power lead which would connect to the additional shifters which might be employed. Although not shown on the diagram for purposes of clarity, indicating lights operated by switches such as switch 23 of FIGURE 1, would be part of the control panel assembly. Remote operation of shifters 70-78 may be accomplished by utilizing alternate contacts on the control switches. The righthand contacts of all switches of FIGURE 7 as represented by 79 of switch S74 would be connected to a remote control panel which would have corresponding switches on it with positive battery.

In the arrangement illustrated by FIGURE 7 switches S74 and S78 are shown in the operating positions for the energized condition of shifters 74 and 78. Receiver R2 is thus connected to operate with antenna A2, the circuit being leads 94, 95, shifter 74, and leads 96 and 97; and receiver R3 is connected to operate with antenna A3, the circuit being via leads 88, 89, 90, shifter 78, and leads 91, 92, and 93. If only the three-by-three arrangement shown is involved, leads 80, 81, 82, 83, 84, and 85 would be connected to ground, and with the other switches in the open position, receiver R1 and antenna A1 would be grounded. By selecting the proper switches any one of the receivers may be connected to any one of the antennas. Terminal 99 represents the shorting elements previously described in connection with FIGURES 1 and 3.

In addition to the many advantages Which will be readily apparent to those skilled in the art, the circuit shifter herein described is readily adapted to pressurized vacuum-packaging. The feature of low-power requirements renders the instant shifter especially adaptable for use in coaxial cross-bar circuit configurations requiring control from remote points.

Although there have been described in this specification only two embodiments of this invention it will be obvious to those skilled in the art that other embodiments are possible Without departing from the scope and intent of coverage of this patent which should be limited only by the appended claims. As an obvious example, the shifter may be employed for use with any shielded cable or transmission line having one or more spaced interior conductors. The broad features of the invention are equally applicable to wave guides and, consequently, the term circuit shifter is intended to embrace situations incorporating wave guides.

What is claimed is:

l. A coaxial circuit shifting device for selectively moving a first coaxial circuit from a connection with a second coaxial circuit to a connection with a third coaxial circuit, comprising:

first and second metallic body members, said first body member being guidably positioned with respect to said second body member and movable from a first position of rest to a second position of rest on said second body member;

means for moving said first member from said first position to said second position of rest;

first coaxial connecting means having outer and inner conductors for said first circuit mounted within said first body member to provide a coaxial conduit through said first member;

second and third coaxial connecting means having outer and inner conductors mounted within said second body member to provide coaxial conduits through said member, said second and third connecting means being spaced by a distance equal to the travel of the first body member in moving from said first position to said second position, said second and third coaxial connecting means being mounted on said second body member at points thereon to produce alignment of the outer and inner conductors of the first and claim 1 wherein said last mentioned means comprises:

ferromagnetic cup-like members axially slidable and positioned on said center conductors of said second and third coaxial connecting means;

and a permanent magnet member comprising the inner conductor of said first coaxial connecting means.

3. A coaxial circuit shifting device in accordance with claim 1 wherein said last mentioned means comprises:

a fixed center conductor member in said first connector,

and a center conductor of said second and third connectors comprising fixed members and movable members,

said movable members comprising cup-like contact members in sliding telescopic relation to said fixed members, and spring-loading biasing means for urging said contact members axially into electrical contact with the center conductor of said first connector at ositions of alignment.

4. A coaxial circuit interconnecting device comprising:

a fixed metallic body member;

a movable metallic body member guidably positioned in sliding relation on said fixed member;

means for changing the position of said movable member from a first position of rest to a second position of rest, said members being in electrical contact at said rest positions;

a plurality of coaxial circuit connectors mounted on said first and second members and spaced in the direction of travel of said second member by an amount equal to the distance said second member moves between said first and second rest positions, whereby connectors on said movable member are selectively aligned with connectors on said fixed member when the said movable member moves from its first to its second position of rest;

and biasing means urging at least one of the opposing center conductor ends against the corresponding center conductor end at said rest positions.

5. A coaxial circuit interconnecting device in accordance with claim 4, wherein said biasing means comprises a permanent magnet element on one of said center conductor ends, and an axially movable ferromagnetic element on the other of said opposing center conductors.

6. A coaxial circuit shifting switch, comprising:

a first metallic body member;

a second metallic body member positioned in movable guided relation to said first member, including guiding means;

means for moving said second member relative to said first member from a first rest position to a second rest position whereat said bodies are in electrical contact;

at least one coaxial connector positioned on said first body to provide a coaxial circuit element through said body;

at least two coaxial circuit connectors positioned on said second body longitudinally spaced thereon by an amount equal to the distance between rest positions to provide an alignment between said one connector and one of said two connectors at one rest position and an alignment between said one connector and the other of said two connectors at the other rest position;

means comprising the center conductor of said first connector to provide an electrical connection between the opposition center conductors under conditions of alignment to complete a coaxial circuit through said bodies.

7. A coaxial circuit shifting switch in accordance with claim 6 wherein said guiding means comprises:

a camming means to slightly raise the second member above the first member when said second member is moved from said first rest position to said second position;

spring means between said bodies to provide a force urging the bodies toward each other.

Charles Aug. 14, 1956 Modrey Sept. 25, 1956 

1. A COAXIAL CIRCUIT SHIFTING DEVICE FOR SELECTIVELY MOVING A FIRST COAXIAL CIRCUIT FROM A CONNECTION WITH A SECOND COAXIAL CIRCUIT TO A CONNECTION WITH A THIRD COAXIAL CIRCUIT, COMPRISING: FIRST AND SECOND METALLIC BODY MEMBERS, SAID FIRST BODY MEMBER BEING GUIDABLY POSITIONED WITH RESPECT TO SAID SECOND BODY MEMBER AND MOVABLE FROM A FIRST POSITION OF REST TO A SECOND POSITION OF REST ON SAID SECOND BODY MEMBER; MEANS FOR MOVING SAID FIRST MEMBER FROM SAID FIRST POSITION TO SAID SECOND POSITION OF REST; FIRST COAXIAL CONNECTING MEANS HAVING OUTER AND INNER CONDUCTORS FOR SAID FIRST CIRCUIT MOUNTED WITHIN SAID FIRST BODY MEMBER TO PROVIDE A COAXIAL CONDUIT THROUGH SAID FIRST MEMBER; SECOND AND THIRD COAXIAL CONNECTING MEANS HAVING OUTER AND INNER CONDUCTORS MOUNTED WITHIN SAID SECOND BODY MEMBER TO PROVIDE COAXIAL CONDUITS THROUGH SAID MEMBER, SAID SECOND AND THIRD CONNECTING MEANS BEING SPACED BY A DISTANCE EQUAL TO THE TRAVEL OF THE FIRST BODY MEMBER IN MOVING FROM SAID FIRST POSITION TO SAID SECOND POSITION, SAID SECOND AND THIRD COAXIAL CONNECTING MEANS BEING MOUNTED ON SAID SECOND BODY MEMBER AT POINTS THEREON TO PRODUCE ALIGNMENT OF THE OUTER AND INNER CONDUCTORS OF THE FIRST AND SECOND CONNECTORS WHEN SAID FIRST BODY IS IN ITS FIRST POSITION OF REST, AND TO PROVIDE ALIGNMENT OF THE OUTER AND INNER CONDUCTORS OF THE FIRST AND THIRD CONNECTORS AT SAID SECOND POSITION OF REST; SAID INNER CONDUCTORS COMPRISING MEANS TO URGE THEIR CONTACTING AREAS INTO CONTACT WITH ONE ANOTHER AT POSITIONS OF ALIGNMENT. 